A DEAFENING roar tore through the air, a plume of steam rose to join the clouds and a locomotive hurtled into view on September 27, 1825, pulling wagons full of coal, flour and people into Darlington station—and Britain into the modern era. Driven by its inventor, George Stephenson, Locomotion I had set off earlier from Shildon, Co Durham, and would continue onto Stockton: despite the odd hiccup, the world’s first public railway was officially open. Nineteen years later, another train burst into view, this time on canvas, closing in on a hare as it crossed the Maidenhead Bridge. J. M. W. Turner presented his Rain, Steam, and Speed 180 years ago, at the June 1844 Royal Academy exhibition. Long accustomed to capturing Nature’s might—storms, avalanches, raging seas—the artist did the…